This invention relates to the preparation of 2bromoethyl acetate and, more particularly, to an improved process for the preparation of 2-bromoethyl acetate which is more cost effective and which produces this compound in good to excellent yield with excellent purity.
2-Bromoethyl acetate is a compound which is employed in the preparation of 5-[N-(2-acetoxyethyl) acetoxyacetamido]-N,N'-bis(2,3-diacetoxypropyl)-2,4,6triiodoisophthalamide which in turn is an intermediate in the preparation of N,N'-bis(2,3-dihydroxypropyl)-5-[N(2-hydroxyethyl) glycolamido]-2,4,6-triiodoisophthalamide. The latter compound is a nonionic x-ray contrast agent (see Lin U.S. Pat. No. 4,396,598 dated Aug. 2, 1983).
Heretofore, it has been known to prepare 2-bromoalkyl acetates (bromohydrin acetates) from 1,2-diols such as ethylene glycol by reacting the diol with 6 molar hydrogen bromide in acetic acid. Golding et al., J. Chem. Soc. Perkin Trans. I, 1973,1214, Bhat et al. Syn. 142 (1984) and Blomquist et al., J. Am. Chem. Soc. 74, 3636 (1952). This preparation involved the use of anhydrous gaseous hydrogen bromide or a saturated solution of hydrogen bromide in acetic acid and requires removal of the water produced by the reaction.
There has been a need in the art for an improved process for preparing 2-bromoethyl acetate which is more cost effective and produces a product of excellent purity in high yield.